The present invention relates generally to architectural channel shaped weather protection covering products for buildings, particularly surface covering elements for wall and roof sections, and more particularly to weather resistant seams and fastening of adjoining covering elements.
The roofing industry is a highly specialized segment of the building industry. Continuous experimentation in research and development has lead to the development, manufacturing and marketing of architectural sheet metal products such as standing seam roofing, curved standing seam roofing, batten seam roofing, soffit panels, facade panels, ceiling panels, Spanish tile roofing, siding panels, metal shingle roofing, light gauge structural members, and light gauge curved structural members. Examples of these and other similar applications can be found in Sweet's, a catalog distributed nationally each year by F. W. Dodge Company to all major architectural firms and construction companies. Particularly relevant examples are manufactured by Berridge Manufacturing Company, and are advertised in Sweet's catalog at 07610/BER.
The panels or pans that comprise certain of the elements of the architectural roofing system of the present invention are roll formed from coils of flat metal sheets to custom lengths for application to particular buildings. The roofing products related to the present invention were originally used in the high volume markets for the bright colored roofs for the franchise industry and service stations. From that beginning, research and design has lead to the multiplicity of applications which have spread throughout the building industry to include residential applications and historic restoration building products.
The manufacturing process takes a coil of flat sheet metal and converts that coil into pre-treated, pre-finished, fabricated, high quality architectural sheet metal product by running the sheet metal through a continuous coil coating line, slitting line, cut to length line, roll formers, mechanical and hydraulic press breaks, punch presses, stamping and bending fixtures, and a variety of special dies. The sheet metal coils are available in a variety of coatings, colors, finishes, and alloys. All of the metals and finishes are available in flat sheet and coil for local fabrication if in a particular case that is the more desirable method of construction.
The original standing seam roofing system was a revolutionary design and method of production for custom standing seam roofing. As originally developed the panel or pan had 90.degree. upright legs and was roll formed to custom lengths for particular buildings. The panels were held in place with folding anchor clips attached the roof substrate which allowed the panel to move from thermal expansion and contraction. Snap-on seams were used to splice the panels together and to give the appearance of the old standing roofing, which was folded over in a closed seam by sheet metal mechanics with hand tongs.
The older standing seam roofs were made from sheet instead of coil, and were limited in lengths to 10 foot maximum because that was the length of the forming equipment. The development of the panel standing seam roofing roll formed from coil allowed panels and seams to be fabricated in continuous lengths from eave to ridge and eliminated the horizontal splice of the shorter sheets which was a source for leaks. However, although the continuous length standing seam roofing system eliminated the horizontal splices, and in most cases specified application over solid sheeting and 30 pound felt underlayment, the possibility still existed for leaks to occur through the vertical joints or snap-on seams from blowing rain, syphoning, or flooding over the seam. Therefore, even though the unnecessary horizontal seams were eliminated it was possible for water to reach the felt underlayment, and it was further possible if the underlayment was not properly installed or had holes that water could enter the building. These types of leaks could only be discovered after they developed and repairs and replacements in the field had to be performed. Repair of roofing leaks can be time consuming and expensive because it is difficult to locate the exact source of the leak. The water can be syphoned through, or leak through at one point, but then it will travel along the felt or along the underside of the roofing materials and can enter at the building at a completely different location. It is far easier to design and install a leak proof seam, than to locate and repair a leak once it develops.
Prior art solutions to the leakage problems included application of caulking compounds in the top of the seams, and application of a hot melt compound in the top of snap-on seams during the roll form operation. Neither of these solutions was successful. The compound was interrupted at each anchor clip which still allowed water to overflow and to reach the felt underlayment. Although these solutions are unsatisfactory, many roofing companies are still using them.
The inventor of the present application, in an effort to solve the leak problems, redesigned anchor clips with shorter pre-folded legs to allow one upright leg of a roofing panel to be rotated into place under the folded leg of the anchor clip. The shorter legs of the anchor clip then allowed a gasket of some material to have room enough to seal itself against the upright leg of the roof panel below the anchor clip to form a moisture resistant splice of panels and seams completely uninterrupted by the anchor clips. The materials and particular extruded shape for the gasket material in combination with the anchor clips and roofing panel legs is described and claimed in the related patent application, U.S. Pat. No. 4,641,475 by inventor Jack Berridge.
The gasket and snap-on seam cover splice is manufactured in a roll-former which is built to roll form a snap-on seam and insert a vinyl extrusion at the seam at the same time. The vinyl insert is fed into the snap-on seam from a coiled extruded shape approximately mid way through the roll-former, and the metal is closed around it and cut to length in the snap-on seam on cutting equipment. This snap-on tee panel standing seam system has been found to be completely water tight regardless of the amount and direction of water flow. This is a break through for a moisture resistant metal standing seam product.
Although the tee panel standing seam leakage problem was successfully solved by the invention embodied in U.S. Pat. No. 4,641,475 there exist other applications for metal panel weather protection elements where structural requirements are not satisfactorily handled by the tee panels and snap-on seam covers. Certain applications require the metal pan roofing panel to carry a structural load rather than to merely provide a weather proof covering. These structural requirements lead to the development of the present invention of the new zee lock structural standing seam roof panel. In a manner similar to that of the angled anchor clip utilized with the tee panels, the shape of the zee panel allows the upright leg of one panel to be rotated into place under the upright portion of a continuous "zee" rib or a series of "zee" clips depending upon the structural loading requirements of the roof. The upright leg of one panel therefore can be rotated under or fitted over the upright leg of an adjacent panel. Further strength is provided by folding over the edge of one "zee" lock panel to form an integrated roofing unit of two roof panels and continuous zee clip rib or clip elements. The top and bottom of the "zee's" function similar to flanges of I-beam and carry structural loads. Although this design provided superior structural strength in comparison with the tee panel and snap-on seam design embodied in U.S. Pat. No. 4,641,475, the contemporaneously formed seal and snap-on seam utilized in U.S. Pat. No. 4,641,475 cannot be used with the zee panels. The present invention further provides a moisture resistant sealing element specifically for use with the zee panel shape, as will be described in greater detail below.